Electric utilities, fuel use, and responsiveness to fuel prices

This research tests the impact of changes in fuel price to explain fuel use by electric utilities. We employ a three-stage least squares model that explains changes in fuel use as a function of changes in three fuel prices. This model is repeated across sub-samples of data aggregated at the plant level and operating holding company level. We expect that plants and holding companies reduce fuel use when fuel prices rise. Several fuel substitution effects within and across plants and holding companies are demonstrated, as well as several frictions. At the plant level, higher prices of natural gas lead to less natural gas consumption, less coal consumption, and more fuel oil consumption. At the operating holding company level, results demonstrate the inelasticity of coal use and the increases of natural gas in response to higher coal prices. Subsamples demonstrate heterogeneity of results across different plants. Results emphasize that technological, market, and regulatory frictions may hinder the performance of energy policies

A Review on TiO2 Nanotube Film Photocatalysts Prepared by Liquid-Phase Deposition

TiO2 nanotube film is a promising photocatalyst associated with its unique physical and chemical properties such as optic, electronic, high specific surface area. Liquid-phase decomposition provides a feasible way for the preparation of functional thin film. This paper reviews and analyzes the formation mechanism of TiO2 nanotube film by liquid phase deposition. The effect of preparation parameters, such as the kinds of electrolyte solution for the preparation of anodic alumina template, volume fraction of Al2O3 on the template, the concentration of the deposition solution, and heat treatment, on the formation of TiO2 nanotube film has been analyzed. The effects of doping of metallic and nonmetallic elements on the photocatalytic activity of TiO2 nanotube have been discussed

Effect of Parameters of Isopipe on the Quality of Glass Sheet Produced from Overflow Fusion Process by Numerical Simulation

A numerical model for simulation of molten glass flow with semi-implicit method for pressure-linked equations (SIMPLE) and Volume of fluid (VOF) method during the overflow fusion process was carried out by using FLUENT software. The effect of the geometry parameters of the isopipe and flow rate of molten glass on the flow patterns during overflow was investigated. The results showed that the overflow trough depth only had an effect on the flow rate distribution of glass melt around the inlet point. The tilt angle at the top of the trough had a significant effect on flow rate distribution along the length of the trough, and the desired mass distribution was achieved at the tilt angle 4°∼6°. The flow rate had a large influence on the overflow of the molten glass, which had a directive significance to the overflow down draw sheet manufacturing process

Effect of Parameters of Isopipe on the Quality of Glass Sheet Produced from Overflow Fusion Process by Numerical Simulation

A numerical model for simulation of molten glass flow with semi-implicit method for pressure-linked equations (SIMPLE) and Volume of fluid (VOF) method during the overflow fusion process was carried out by using FLUENT software. The effect of the geometry parameters of the isopipe and flow rate of molten glass on the flow patterns during overflow was investigated. The results showed that the overflow trough depth only had an effect on the flow rate distribution of glass melt around the inlet point. The tilt angle at the top of the trough had a significant effect on flow rate distribution along the length of the trough, and the desired mass distribution was achieved at the tilt angle 4°∼6°. The flow rate had a large influence on the overflow of the molten glass, which had a directive significance to the overflow down draw sheet manufacturing process

Improved Thermoelectric Properties in Lu-doped Yb_(14)MnSb_(11) Zintl Compounds

The thermoelectric transport properties of Lu-doped Yb_(14)MnSb_(11) Zintl compounds have been investigated. The electrical conductivity increased and the Seebeck coefficient decreased with increasing Lu doping content, due to an increased carrier concentration. The carrier mobility behavior was in good accordance with the single parabolic band model. It is suggested that Lu doping simply shifts the Fermi energy with the band structure minimally altered. The lattice thermal conductivity roughly decreased via Lu doping. The maximum dimensionless figure of merit ZT of the Lu-doped samples was improved by ∼30% at 670 K, compared with that without doping

Liquid-Metal-Induced Hydrogen Insertion in Photoelectrodes for Enhanced Photoelectrochemical Water Oxidation

Fast charge separation and transfer (CST) is essential for achieving efficient solar conversion processes. This CST process requires not only a strong driving force but also a sufficient charge carrier concentration, which is not easily achievable with traditional methods. Herein, we report a rapid hydrogenation method enabled by gallium-based liquid metals (GBLMs) to modify the prototypical WO3 photoelectrode to enhance the CST for a PEC process. Protons in solution are controllably embedded into the WO3 photoanode accompanied by electron injection due to the strong reduction capability of GBLMs. This process dramatically increases the carrier concentration of the WO3 photoanode, leading to improved charge separation and transfer. The hydrogenated WO3 photoanode exhibits over a 229% improvement in photocurrent density with long-term stability. The effectiveness of GBLMs treatment in accelerating the CST process is further proved using other more general semiconductor photoelectrodes, including Nb2O5 and TiO2

Liquid-Metal-Induced Hydrogen Insertion in Photoelectrodes for Enhanced Photoelectrochemical Water Oxidation

Fast charge separation and transfer (CST) is essential for achieving efficient solar conversion processes. This CST process requires not only a strong driving force but also a sufficient charge carrier concentration, which is not easily achievable with traditional methods. Herein, we report a rapid hydrogenation method enabled by gallium-based liquid metals (GBLMs) to modify the prototypical WO3 photoelectrode to enhance the CST for a PEC process. Protons in solution are controllably embedded into the WO3 photoanode accompanied by electron injection due to the strong reduction capability of GBLMs. This process dramatically increases the carrier concentration of the WO3 photoanode, leading to improved charge separation and transfer. The hydrogenated WO3 photoanode exhibits over a 229% improvement in photocurrent density with long-term stability. The effectiveness of GBLMs treatment in accelerating the CST process is further proved using other more general semiconductor photoelectrodes, including Nb2O5 and TiO2

Temporal variations of carbon and water fluxes in a subtropical mangrove forest: Insights from a decade-long eddy covariance measurement

Mangroves, highly efficient ecosystems in sequestering CO2, are strongly impacted by climate change. The lack of long-term observation in mangroves hinders the evaluation of seasonal and inter-annual variability in carbon and water fluxes and their responses to various environmental drivers. In this study, we measured net ecosystem CO2 exchange and evapotranspiration between the atmosphere and subtropical mangroves using the eddy covariance technique over a decade (2010–2019) in southern China. This mangrove forest acted as a strong CO2 sink, with annual net ecosystem production (NEP) ranging from 622.5 to 832.8 g C m−2 year−1. The annual evapotranspiration (ET) varied between 934.6 and 1004.9 mm year−1. During the study period, ET consistently remained higher in the wet season (May to October) compared to the dry season, while NEP did not exhibit consistent seasonal variation. Path analysis indicated that during the dry season, NEP was primarily influenced by global solar radiation and vapor pressure deficit. However, in the wet season, NEP was regulated by a combination of global solar radiation, vapor pressure deficit, air temperature, and tidal inundation time. Additionally, the promoting effect of global solar radiation on NEP decreased in the wet season, while the inhibitory influences of higher temperature and vapor pressure deficit on NEP intensified during the period. Unlike NEP, the dominant factors affecting ET (global solar radiation, air temperature, and vapor pressure deficit) and their intensities remained relatively consistent during both seasons. Furthermore, the relative importance of global solar radiation on NEP and ET increased over the decade, while the influence of tidal inundation time diminished. This study not only improves the understanding of the response of subtropical mangroves to climate change but also provides a valuable benchmark dataset to validate the interannual variability of mangrove carbon and water fluxes estimated from the models.ISSN:0168-1923ISSN:1873-224